We're pulling for him. Donald Trump feeling the heat. The first attack ad of the campaign targeting trump. Showing him praising democrats, including Hillary Clinton. Jon Karl in Martha's vineyard this morning. Reporter: Trump may be facing new attacks this morning. But he continues to defy split kl gravity. The latest polls show him with a commanding lead in the early primary states. It's the first attack ad against Donald Trump of the 2016 campaign. In many cases, I probably identify more as a democrat. It just seems that the economy does better under the democrats. Reporter: Senator Rand Paul aimed squarely at the front-runner, using trump's own words against him. The Donald's reaction? He swatted away Paul in an interview on CNN. He's failing in the poll. Weak in the military. I thing he's far better doctor than a senator. He's a mess. Reporter: Attacking trump has been a ticket to oblivion so far. Rick Perry and Lindsey graham are at the bottom of the polls. Teflon truch is still on top. Polls since this controversial performance last week, he holds a commanding lead. In Iowa, trump at 22%. With Dr. Ben Carson in second at 14%. Scott walker now in third. While trump fends off his republican rivals, Wednesday Jeb bush lashed out after the democratic front-runner. You have Hillary Clinton, the secretary of state, dealing with confidential informing. Thinking it was okay to use a private server? Reporter: Hillary Clinton is now reportedly turned over that private e-mail server that she refooufed to turn over for so long to the justice department. That happened yesterday, we're told. New polls in New Hampshire and Iowa show Hillary is facing a tough challenge from her long-shot challenger Bernie sanders. Those Numbers tightening. Thank you. Now to the toxic chemical

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